You can certainly use a sparge arm. Lots of folks just keep the sparge water an inch or so above the grain bed without an arm or sprinkler so to speak. Basicly you can just gently add the sparge water so as not to drill down into the grain bed.

No need for a sparge arm and it would actually get in your way the way I batch sparge. I just dump the sparge water on top, stir the hell out of the grains to mix the water and extract the sugars, vorlauf to set the grainbed, drain, repeat if necessary.

Batch sparging is just the simplest possible version of sparging. You pour in the sparge water, you stir, you vorlauf & lauter the second runnings of wort. (Obviously, if you do more than one sparge, this would be repeated- I don't).

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“Malt does more than Milton can / To justify God’s ways to man”

ok...so I have been doing it wrong. The saison I made on Saturday...I just poured the sparge in the MLT stirred, vorlauf and to boil. This is much faster than how I was doing it previously...Im sure my efficiency shot through thte roof too!